Internal-combustion turbine with plural generators selectively operable



1953 B. C. RENNIE ETAL INTERNAL-COMBUSTION TURBINE WITH PLURAL GENERATORS SELECTI-VELY OPERABLE Filed y 20 1950 2 Sheets-Sheet l BASIL. CAMERON RENNIE JOHN HAROLD WEAVING Dec. 15, 1953 B N E C. RE NI ETAL INTERNAL-COMBUSTION TURBINE WITH PLURAL GENERATORS SELECTIVELY OPERABLE Filed July 20, 1950 2 Sheets-Sheet 2 ATTORNEY BASIL CAMERON RENNIE JOHN HAROLD WEAVING Patented Dec. 15, 1953 INTERNAL-COMBUSTION TURBINE WITH PLURAL GENERATORS SELECTIVELY OPERABLE :Basil C. Rennie, Cambridge, and John H. Weaving, Moseley, Birmingham, England, assignors to The Austin Motor Company Limited, Birmingham, England Application July 20, 1950, Serial No. 174,812

8 Claims. 1

This invention relates to internal combustion turbines.

It is well known, that internal combustion turbines, designed to give maximum efliciencyat full loads, have considerably reduced efficiency when operating under part load conditions, and the object of the present invention is to overcome or minimise this disadvantage.

Internal combustion turbines can be run on part loads by (a) reducing the pressure ratio, (1)) reducing the working temperature, or reducing the amount of air used, or by a combination of any of these three well-known methods.

In an internal combustion turbine according to the present invention, means are provided whereby the number of turbine nozzles in use can be varied, the arrangement being such as to enable the fiow of air to be reduced without substantially altering the operating temperatures and pressures. Preferably also the control would be such as to maintain the balance of the turbine rotor under all operating conditions.

The invention will now be described with reference to various applications shown, diagrammatically and by way of examples, in the accompanying drawings, in which- Figs. 1 and 2 are a side elevation and an end elevation respectively of an internal combustion turbine.

Figs. 3 and 4 are similar views to Figs. 1 and2 respectively, but illustrate a modified arrangement.

Fig. 5 is a side elevation of an internal combustion turbine but showing a further modification.

Figs. 6 and '7 are similar views to Figs. 1 and 2 respectively but illustrate a further modified arrangement.

Figs. 8 and 9 are similar views to Figs. 1 and 2 respectively but showing yet a further modified arrangement.

Fig. 10 is a diametrical section of a variable capacity compressor, of the centrifugal type, suitable for supplying air to any of the arrangements shown in the previous figures of the drawings.

Referring to Figs. 1 and 2 of the drawings, i represents a compressor supplying air to combustion chambers 2 from which the heated air and products of combustion pass to the nozzles 4 of a turbine 5 so as to drive the turbine rotor 6 from which power may be taken. The combustion chambers 2 have their inlets 1 controlled by valves 8 so that the supply of air to each such chamber can be varied or cut oii without altering the operating temperatures and pressures of the other two combustion chambers. The combustion chamber outlets 9 are flared so that each embraces or includes a number of turbine nozzles 4, or a number of sections of a nozzle ring.

The arrangement in Figs. 3 and 4. is similar to that shown in Figs. 1 and 2 except that the outlet 9 of each combustion chamber 2 has two branches which supply diametrically opposed turbine nozzles i, so that any valve 8 can be closed without disturbing the balance of the load on the turbine rotor .6. With this arrangement one, two or all three combustion chambers 2 may be operative at any time to suit requirements, the balance of the load on the turbine rotor being preserved since each valve 8 controls the air supply to a combustion chamber feeding diametrically opposed, or a balanced set of, turbine nozzles 4.

In Fig. 5 the arrangement is similar to that shown in Fig. 1 except that the valves 8 are in the outlets 9 of the combustion chambers 2, in stead of the inlets 1, so that the nozzles l are directly controlled by the valves.

Referring now to the modification shown in Figs. 6 and '7, the arrangement includes four combustion chambers 2, each controlled by a valve 8 in its inlet 1, as shown in full lines, or by a valve 8 in its outlet 9, as shown in chain dotted lines, and each such outlet feeds a single nozzle 4 or a set of such nozzles. With this arrangement the valves 8 associated with either of the diametrically opposed pairs of combustion chambers 2 can be closed without causing a state of unbalance of the load on the turbine rotor 6.

The modification shown in Figs. 8 and 9 includes only one combustion chamber 2 and its outlet 9 has three branches each fitted with a valve 8 through which the various nozzles 4, or sets of nozzles, are supplied and controlled.

With any of the arrangements above described, it will be understood that the characteristics of the compressor would require to be controlled to suit the number of nozzles in use at any time. If the compressor is of the positive displacement type, its delivery would be controlled by varying its speed. If, however, the compressor is of the centrifugal type, as shown, means would be required to provide for varying its capacity to suit the. number of turbine nozzles in use at any time, since to vary the speed of this type of compressor would alter the compression ratio and reduce the eificiency.

The means for varying the capacity of the centrifugal compressor may, as shown in Fig. 10, comprise a shroud disc l0 which is axially adjustable in relation to the rotary impeller H of the compressor to vary the effective cross sectional area of the air passages between the impeller blades l2. The shroud disc II] is radially slotted from its periphery to a hollow central boss 13 so as to interdigitate with the radial blades I2 of the impeller I l, and said hollow central boss l3 works as a hollow piston upon the headed end H of a spindle l5 which is held against axial movement in an axial bore in the impeller shaft 16 by a screw IG The shroud disc H] is urged toward the disc of the impeller II by a helical compression spring I I which encircles the spindle l5 and operates between the head [4 thereof and a washer l8 which is retained in the rear end of the boss 13 by a circlip I 9. In order to adjust the shroud disc l8 away from the disc of the impeller H, and thereby alter the effective crosssectional area of the air passages between the impeller blades I2, inlet casing and shroud disc l0, oil or other appropriate fluid under pressure is admitted to the chamber afforded in the hollow piston or boss l3 and in front of the headed end Hi of the spindle l5, so as to overcome, to the requisite degree, the compression spring [1. Such oil or working fluid is admitted through an axial passage 2| and lateral ports 22 in the spindle l5, which ports 22 are in communication, through ports 23 in the impeller shaft l6 and associated bearing packing 24 and liner 25, with a pressure supply pipe 26.

Having fully described our invention, what we claim and desire to secure by Letters Patent is:

1. An internal combustion turbine comprising a variable delivery compressor through which all of the air must flow, means to vary the volumetric capacity of the compressor while maintaining substantially the same outlet pressure therefrom, combustion chamber means supplied with from said compressor, and a turbine in which heated air from the combustion chamber means is expanded to drive the turbine rotor, turbine nozzles in communication with said combustion chamber means for directing heated air to the turbine, control means wher by the number of turbine nozzles in use can be varied so as to enable the compressor delivery to be reduced to compensate for the reduction in turbine nozzles without altering the operating temperatures and pressures.

2. In an internal combustion turbine comprising a variable delivery compressor through which all of the air must flow, means to vary the volumetric capacity of the compressor while maintaining substantially the same outlet pressure, a number of combustion chambers supplied with air through inlets from said compressor, and a turbine in which heated air from the combustion chambers is expanded to drive the turbine rotor, turbine nozzles in communication with said combustion chambers for directing heated air to the turbine, each combustion chamber feeding certain of the turbine nozzles, valve means selectively controlling the combustion chamber inlets so that the supply of air to any of the combustion chambers can be cut ofif at will thus rendering ineffective the corresponding nozzles of the turbine and enabling the compressor delivery to be reduced to compensate for the reduction in turbine nozzles without altering the operating temperatures and pressures.

3. An internal combustion turbine including a variable delivery compressor through which all of the air must flow, means to vary the volumetric capacity of the compressor while maintaining substantially the same outlet pressure, a number of combustion chambers supplied with air through inlets from said compressor, turbine nozzles in communication with said combustion chambers, a turbine in which heated air from the combustion chambers is expanded to drive the turbine rotor, each combustion chamber feeding a balanced complement of the turbine nozzles, and valve means selectively controlling the com-' bustion chamber inlets so that the supply of air to any of the combustion chambers can be cut oiT at will thus rendering ineffective the corresponding nozzles of the turbine and enabling the compressor delivery to be reduced to compensate for the reduction in turbine nozzles without altering the operating temperatures and pressures.

4. An internal combustion turbine including a variable delivery compressor through which all of the air must flow, means to vary the volumetric capacity of the compressor while maintaining substantially the same outlet pressure therefrom, a number of combustion chambers supplied with air through inlets from said compressor, turbine nozzles in communication with said combustion chambers, a turbine in which heated air from the combustion chambers is expanded to drive the turbine rotor, each combustion chamber feeding a balanced complement of the turbine nozzles, and valve means selectively controlling the combustion chamber outlets so that the supply of heated air to any such set of turbine nozzles can be cut off at will enabling the compressor delivery to be reduced to compensate for the reduction in turbine nozzles without altering the operating temperatures and pressures.

5. An internal combustion turbine comprising a variable delivery compressor through which all of the air must flow, means to vary the volumetric capacity of the compressor while maintaining substantially the same outlet pressure, a single combustion chamber supplied with air from said compressor and having a number of outlets, a turbine in which heated air from the combustion chamber is expanded to drive the turbine rotor, nozzles in communication with said outlets for directing heated air to said turbine, and variable means selectively controlling the said outlets so that the supply of heated air through any of said outlets can be out ofi at will thus rendering ineffective the corresponding nozzles of the turbine and enabling the compressor delivery to be reduced to compensate for the reduction in turbine nozzles without altering the operating temperatures and pressures.

6. An internal combustion turbine comprising a centrifugal compressor through which all of the air must flow through a passage, combustion chamber means supplied with air by said compressor, a turbine in which heated air from the combustion chamber means is expanded to drive the turbine rotor, nozzles in communication with said combustion chamber for directing heated air to said turbine, control means whereby the number of turbine nozzles in use can be varied, and a shroud axially adjustable in relation to the bladed impeller of the compressor to vary the effective cross-sectional area of air passages between the impeller blades so that the compressor delivery can be varied to suit the number of turbine nozzles in use and without altering the operating temperatures and pressures.

7. An internal combustion turbine comprising a centrifugal compressor, combustion chamber means supplied with air by said compressor, a turbine in which heated air from the combustion chamber means is expanded to drive the turbine rotor nozzles in communication with said combustion chamber for directing heated air to said turbine, control means whereby the number of turbine nozzles in use can be varied, and a shroud axially adjustable in relation to the bladed impeller of the compressor to vary the effective cross sectional area of air passages between the impeller blades so that the compressor delivery can be varied to suit the number of turbine nozzles in use and without altering the operating temperatures and pressures.

8. An internal combustion turbine comprising a compressor for supplying gas, means to vary the quantative capacity of the compressor while maintaining substantially the same outlet pressure, a combustion chamber in communication with said compressor for receiving the compressed gas from said compressor, a turbine, turbine nozzles in communication with said combustion chamber directing heated gas from said combustion chamber to said turbine, and manually controlled means for preventing the flow of gas through some of said nozzles, the means to vary the quantity of gas from said compressor and the manually controlled means being arranged for maintaining constant operating conditions of temperature and pressure in the chamber and nozzles.

BASIL C. RENNIE.

JOHN H. WEAVING.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,442,876 Hartman Jan. 23, 1923 1,986,435 Heinze Jan. 1, 1935 2,056,198 Lasley Oct. 6, 1936 2,575,683 Price Nov. 20, 1951 FOREIGN PATENTS Number Country Date 735,857 France Sept. 16, 1932 387,166 Germany Dec. 21, 1923 

